Spell Damage Increase

A must have for any aspiring magic user, spell damage increase does exactly what you expect. It increases the damage of your spells. Spell damage increase, or SDI, is found on many artifacts and is uncapped. It can also be increased by the free skill, Inscription, which can give up to a 12% bonus at skill level 120.

See BIS:SDI for the highest SDI items you can get for each slot

Spells that Benefit from SDI

Magery

• Magic Arrow
• Lightning
• Harm
• Chain Lightning
• Flame Strike
• Meteor Swarm
• Energy Bolt
• Explosion
• Fireball

Mysticism

• Bombard
• Eagle Strike
• Hail Storm
• Nether Bolt
• Nether Cyclone
• Spell Plague

Necromancy

• Poison Strike
• Wither

Spellweaving

• Essence of Wind
• Thunderstorm
• Wildfire
• Word of Death

Misc

• Flaming Shot – Archery Mastery
• Weapon on hit properties
• Death Ray – Magery Mastery
• Holy Fist – Chivalry Mastery
• Nether Blast – Mysticism Mastery